LOUDON, N.H.—The Hendrick Motorsports car of Jimmie Johnson was too low in post-qualifying inspection, which forced NASCAR to disallow his qualifying time and send the car to the rear of the of the field for the Sprint Cup Series race Sunday.

Johnson had qualified with the second-fastest speed, just 0.02 mph slower (four-thousandths of a second) than pole-sitter Brad Keselowski during time trials Friday afternoon around the 1.058-mile track.

Jimmie Johnson will start at the back of the field on Sunday. (AP Photo)

A five-time Cup champion, series points leader Johnson had trouble getting through tech prior to his qualifying lap. He said his team had to cut one-16th of an inch off the side skirt and was a pound too light.

“We had to go through twice and that is usually big trouble for teams,” Johnson said after the lap. “We were able to get it done quickly and get out just in time. With all that being said, it just added a lot of stress.”

Johnson crew chief Chad Knaus said the front end was misassembled when switching setups from practice to qualifying. That caused the initial problems as well as the post-qualifying problems, where the entire front end was too low.

“We were able to get the car right (for qualifying), but it just wasn’t exactly right and we weren’t going to know until after qualifying once we started tearing it apart what the problem was,” Knaus said.

“There was a mis-assembly issue with the left front, and that’s why the heights were so messed up when we went through initial inspection and it came back to bite us.”

Knaus said the team will be able to add back to the side skirt on the right side of the car that it cut off to get through tech.

It is not unprecedented for a car to settle on its shocks and springs after a qualifying lap, and teams periodically are found to be too low following qualifying.

“We saw that there was an issue (in prequalifying tech)—the left side was real high and the right side was real low,” Knaus said. “We knew there was something that just wasn’t jiving right. We were able to get through but afterward, the car settled a little bit.

“At a track like New Hampshire, you run a lot of shock and you run a lot of front rebound and it takes a little bit (of time) for the cars to come up. With the way that we’re measuring the heights now, you don’t really have a lot of room for error and we just had a little error.”

Johnson then had more stress as his qualifying speed was disallowed, which put him 43rd in the 43-car lineup for the Camping World RV Sales 301.

Kurt Busch, who was third-quickest in qualifying, will start next to Keselowski on the front row.

The disallowing of a qualifying time for a height infraction is standard NASCAR procedure with no additional penalties such as fines, points reductions or suspensions.